At the end of the defrost cycle, the electric heaters (if installed) will be deenergized; the reversing valves switch and the outdoor-fan motor will be energized. The unit will now operate in the Heating mode.

If the space thermostat is satisfied during a defrost cycle, the unit will continue in the Defrost mode until the time or temperature constraints are satisfied.

Automatic changeover

When the system selection switch is set at AUTO. position, unit automatically changes from heating operation to cooling operation when the temperature of the conditioned space rises to the cooling level setting. When the temperature of the conditioned space falls to the heating level setting, unit automatically changes from cooling to heating operation (with a 3°F deadband in between).

Continuous air circulation

Turn unit power on. Set system control at OFF position. Set fan switch at ON position. The indoor-fan contactor is energized through the thermostat switch and the indoor fan runs continuously.

Cycle-LOCprotection

If unit operation is interrupted by an open high-pressure switch, low-pressure switch, indoor coil freeze stat, or by compressor internal line-break device (overcurrent or overtemperature), and compressor is calling for either cooling or heating, Cycle-LOC protection device simultaneously locks out unit and lights a warning light on the thermostat. Restart the unit by manually turning thermostat to OFF and then to ON position. If any of the protective devices opens again, the unit continues to lock out until corrective action is taken.

NOTE: If the unit fails to operate due to compressor over-current condition, restart by manually resetting circuit breakers at the unit. Restart cannot be accomplished at the room thermostat.

Emergency heat

If compressor is inoperative due to a tripped safety device (high or low pressure, indoor coil freeze stat, overcurrent, or overtemperature), the Cycle-LOC device locks out the compressor and lights a warning light on the room thermostat. When the switch is on (thermostat is set to the EM HT position), compressor circuit and outdoor thermostats are bypassed, and the second stage of thermostat energizes the indoor blower and the electric resistance heaters.

548J

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Bryant 548J manual Automatic changeover, Continuous air circulation, Cycle-LOCprotection, Emergency heat

548J specifications

The Bryant 548J is a high-efficiency gas furnace that combines advanced features and technologies to provide exceptional heating performance. Designed for residential applications, the furnace is notable for its ability to deliver consistent warmth while ensuring energy efficiency and reliability.

One of the main features of the Bryant 548J is its ultra-high efficiency rating, which allows homeowners to save significantly on energy costs. With an Annual Fuel Utilization Efficiency (AFUE) rating of up to 96.5%, this furnace is designed to convert a large portion of fuel into usable heat. This is a remarkable characteristic that not only reduces utility bills but also contributes to a lower environmental footprint.

The 548J is equipped with a modulating gas valve and a variable-speed blower motor. The modulating gas valve enables the furnace to adjust its heating output based on real-time temperature demands, ensuring a more precise heating experience. This results in reduced temperature fluctuations within the home, providing a comfortable living environment. The variable-speed blower motor works in tandem with the modulating valve, facilitating improved air circulation and efficient temperature control.

Additionally, the Bryant 548J features a durable and compact design, making it suitable for various installation spaces. Its quality construction ensures longevity, while the optional stainless steel heat exchanger enhances its reliability. The furnace also includes a quiet operation mode, which minimizes noise levels, ensuring that the unit works quietly in the background without disturbing the household's peace.

Integration with smart home technology is another advantage of the Bryant 548J. Homeowners have the option to connect the furnace to a Wi-Fi-enabled thermostat, allowing for remote temperature control and monitoring. This feature offers enhanced convenience and the ability to optimize energy use according to a homeowner’s schedule.

For peace of mind, the Bryant 548J comes with a range of warranties, protecting the consumer's investment. Bryant’s commitment to quality is reflected in their extensive primary heating testing procedures, which ensure that each unit meets strict performance criteria before it reaches the customer.

In summary, the Bryant 548J is an efficient and reliable gas furnace that embodies advanced heating technology. With features such as high AFUE ratings, modulating gas valves, variable-speed blowers, and smart home compatibility, it stands out as a formidable option for modern residential heating solutions.